1. Field of the Invention
The present invention relates to a treatment apparatus and a treatment method, for example, a baking unit for heating a substrate such as a semiconductor wafer, a resist coating unit for coating the substrate with resist, a developing unit for developing the substrate, or the like.
2. Description of the Related Art
In processes of semiconductor device fabrication, the photolithography process is conventionally performed to form a resist pattern on a surface of a substrate such as a semiconductor wafer (referred to as xe2x80x9ca waferxe2x80x9d hereinafter).
In the photolithography process, there are a resist coating process for coating a wafer with a resist, an exposing treatment process for exposing the resist-coated wafer, and a developing treatment process for developing the wafer. Before and/or after each treatment process, a heat treatment (bake) is suitably performed to the wafer as needed. More specifically, so-called a dehydrating-bake for drying the wafer, so-called a pre-bake for removing the resist solvent in the resist by heating, so-called a post-exposure-bake (referred to as xe2x80x9cPEBxe2x80x9d hereinafter) which is performed between the exposing treatment process and the developing treatment process, a post-bake which is performed after completing the developing treatment process, and the like.
Explaining these in order of treatment, first of all, the dehydrating-baked wafer is coated with a resist. Next, after the above wafer is pre-baked, the wafer is exposed by an exposing unit. Sequentially, after the exposed wafer is heat-treated by PEB, the wafer is treated with the predetermined development, thereafter the post-bake is performed.
In the aforesaid processes, where chemically-amplifying-type resist is used as a resist, acid is generated in the resist during the exposing treatment. The wafer is heat-treated by PEB, thereby catalytic reaction in the acid is activated, so that solubility or insolubility of chemically-amplifying-type resist to the developing solution is accelerated. In the heat treatment by PEB, however, only a mounting table is heated in a treatment chamber in the conventional art, therefore relative humidity lowers and an atmosphere is extremely dry in the treatment chamber. When the inside of the treatment chamber becomes dry, water is removed from the resist on the wafer, so that there arises a possibility that the required resist pattern can not be formed.
In the aforesaid resist coating process, the developing treatment process, or the like, since temperature or humidity of the atmosphere during the treatment affects on the film-thickness and uniformity in the resist and developing solution, the temperature and humidity need to be adjusted to predetermined values. Therefore, an atmospheric gas which is air-conditioned through, for example, a humidifying section where water is heated by a heater to evaporate and additionally a heating section to control temperature is sent through ducts into the treatment chambers in which resist-coating and developing treatment are performed. However, where the apparatus is stopped driving, immediately after the heater of the humidifying section is off, the water therein is still warm. Thus, a large amount of water vapor still evaporating from the humidifying section condenses into dew and remains on the inner wall of the duct. As a result, when the apparatus is resumed driving, the water in the duct evaporates, therefore it occasionally takes long time till humidity of the air sent into the treatment chamber becomes stable. Further, a temperature controller which forms the heating section and the humidifying section is generally provided outside the treatment chamber, thus the temperature on the outlet side of the temperature control section happens to be unstable depending on the outside atmosphere. Therefore, where the temperature control is performed, for example, based on the value of a temperature sensor attached on the outlet side of the temperature control section, the temperature of the atmospheric gas sent into the treatment chamber often becomes unstable.
In the coating and developing system for performing a series of processes as described above, for example, an atmospheric gas which is controlled in temperature and humidity is sent from one supply source to a plurality of treatment chambers for developing treatment. The coating and developing system, however, has a heat treatment unit in addition to the treatment chambers for performing developing treatment and resist-coating. Therefore, in the above treatment chamber disposed near the heat treatment unit or in the treatment chamber into which the atmospheric gas flows through a passage near the heat treatment unit, the atmospheric gas rises in temperature, thereby the atmosphere of each chamber varies in temperature among the treatment chambers. As a result, there is a problem that the thickness of coated-film differs among the treatment chambers and the treatment can not be uniformly carried out. It is conceivable to control the atmospheric gas in temperature and humidity individually for each treatment chamber, but this method requires high cost and a large space. Furthermore, for uniform treatment, it is also conceivable to control individually the rotational frequency of wafers at the time of coating in correspondence with the temperature and humidity of the atmospheric gas. This requires adjustment of treatment conditions or the like in each treatment chamber, making a disadvantage due to the complicated procedures. Another disadvantage is that the treatment becomes unstable because heat can not be uniformly received from the heat source.
An object of the present invention is to provide a treatment apparatus and a treatment method capable of forming a required resist pattern, without water in resist being taken out.
Another object of the present invention is to provide a treatment apparatus and a treatment method in which humidity of an atmospheric gas can be quickly stable at the time of resumption of driving the treatment apparatus.
Still another object of the present invention is to provide a treatment apparatus and a treatment method in which temperature control of the atmospheric gas can be stably performed.
Yet another object of the present invention is to provide a treatment apparatus and a treatment method capable of controlling temperature and humidity of the atmosphere respectively for a plurality of treatment chambers, thereby controlling atmospheres of all treatment chambers into the same and controlling atmospheres differently for each treatment chamber according to treatment matters in the respective treatment chambers.
To solve the above disadvantages, the first aspect of the present invention, in an apparatus to treat a substrate, includes a treatment chamber for treating the substrate and a humidifying mechanism for supplying humidified gas into the treatment chamber.
The second aspect of the present invention, in an apparatus to treat a substrate, includes a treatment chamber for treating the substrate, a gas supply passage for supplying an atmospheric gas into the treatment chamber, a heating section provided on the gas supply passage for heating the gas, a humidifying section provided on the gas supply passage for humidifying the gas, at least one blowing section for blowing gas in the gas supply passage, and a control section which stops the humidification of the gas performed by the humidifying section after completion of the substrate treatment in the treatment chamber, blows gas in the treatment chamber by the blowing section, and then stops blowing conducted by the blowing section.
The third aspect of the present invention, in an apparatus to treat a substrate, includes a treatment chamber for treating the substrate, a gas supply passage having a connecting section connected to the treatment chamber for supplying an atmospheric gas through the connecting section into the treatment chamber, a heating section having an outlet connected to the gas supply passage and heating the gas to supply from the outlet into the gas supply passage, a first temperature detecting section disposed at or in the vicinity of the heating section, a second temperature detecting section disposed at or in the vicinity of the connecting section of the gas supply passage, and a control section to control heating of the gas conducted by the heating section based on the detected results of the first and second temperature detecting sections.
The fourth aspect of the present invention, in an apparatus to treat a substrate, includes a plurality of treatment chambers for treating the substrate, a gas source for sending the temperature-controlled atmospheric gas to each treatment chamber, and a plurality of atmosphere control sections provided in each treatment chamber and temperature-controlling the atmospheric gas sent from the gas source to supply into each treatment chamber.
The fifth aspect of the present invention, in a method to treat a substrate, includes (a) a process of treating the substrate in a treatment chamber and (b) a process of supplying the humidified gas into the treatment chamber during the process (a).
The sixth aspect of the present invention, in a method to treat a substrate, includes (a) a process of treating the substrate in a treatment chamber, (b) a process of sending a heated and humidified atmospheric gas through a gas supply passage into the treatment chamber during the process (a), (c) a process of sending an atmospheric gas which is stopped being humidified through the gas supply passage into the treatment chamber after the process (a), and (d) a process of stopping sending the atmospheric gas through the gas supply passage into the treatment chamber after the process (c).
The seventh aspect of the present invention, in a method to treat a substrate, includes a process of sending a temperature-controlled atmospheric gas from a gas source to a plurality of treatment chambers for treating the substrates and a process of temperature-controlling the atmospheric gas sent from the gas source for each treatment chamber and supplying the gas to each treatment chamber.
In the present invention, when the substrate is heated in the treatment chamber after, for instance, the resist-coated substrate is exposed, the humidified gas is supplied into the treatment chamber, thereby preventing relative humidity from lowering and the inside of the treatment chamber from drying. Accordingly, the substrate can be heated in the treatment chamber having the humidified atmosphere, so that water in the resist is not taken out. Consequently, the required resist pattern can be formed.
Further, in the present invention, when supplying of the atmospheric gas into the treatment chamber is stopped, the blowing section is kept in operation while a water temperature in the humidifying section is still high and stopped after the water temperature goes down to a certain degree. Therefore, when the treatment apparatus resumes operation, the inside of the gas supply passage is in a dry condition, which allows the humidity of the atmospheric gas to be stable, so that the operation can be immediately resumed.
Furthermore, according to the present invention, when the gas is controlled over temperature by the heating section of the temperature control section, the temperature control is performed based on both values of the temperature in the vicinity of the outlet of the temperature control section and the temperature in the treatment chamber, therefore the temperature of the atmospheric gas supplied into the treatment chamber becomes stable.
Yet, according to the present invention, the temperature of the atmospheric gas is roughly controlled in the gas source and is finely controlled in each atmosphere control section of a plurality of the treatment chambers, therefore the gas can be set into a required atmosphere in each treatment chamber. Accordingly, even if, for example, a received heat-influence from the heat treatment unit differs in degree among the treatment chambers in accordance with difference of position to the heat treatment unit, when the treatment chambers perform the same treatment, the atmospheric temperatures can be kept equal. As a result, the treatment is uniformly performed with respect to the treatment differed by the atmospheric temperature.
These objects and other objects and advantages of the present invention can be easily confirmed with the following description and the accompanying drawings.